Rechercher une page de manuel
XML::LibXML::Pattern.3pm
Langue: en
Version: 2009-10-07 (ubuntu - 24/10/10)
Section: 3 (Bibliothèques de fonctions)
NAME
XML::LibXML::Pattern - XML::LibXML::Pattern - interface to libxml2 XPath patternsSYNOPSIS
use XML::LibXML; my $pattern = new XML::LibXML::Pattern('/x:html/x:body//x:div', { 'x' => 'http://www.w3.org/1999/xhtml' }); # test a match on a XML::LibXML::Node $node if ($pattern->matchesNode($node)) { ... } # or on a XML::LibXML::Reader if ($reader->matchesPattern($pattern)) { ... } # or skip reading all nodes that do not match print $reader->nodePath while $reader->nextPatternMatch($pattern); $pattern = XML::LibXML::Pattern->new( pattern, { prefix => namespace_URI, ... } ); $bool = $pattern->matchesNode($node);
DESCRIPTION
This is a perl interface to libxml2's pattern matching support http://xmlsoft.org/html/libxml-pattern.html. This feature requires recent versions of libxml2.Patterns are a small subset of XPath language, which is limitted to (disjunctions of) location paths involving the child and descendant axes in abbreviated form as described by the extended BNF given below:
Selector ::= Path ( '|' Path )* Path ::= ('.//' | '//' | '/' )? Step ( '/' Step )* Step ::= '.' | NameTest NameTest ::= QName | '*' | NCName ':' '*'
For readability, whitespace may be used in selector XPath expressions even though not explicitly allowed by the grammar: whitespace may be freely added within patterns before or after any token, where
token ::= '.' | '/' | '//' | '|' | NameTest
Note that no predicates or attribute tests are allowed.
Patterns are particularly useful for stream parsing provided via the "XML::LibXML::Reader" interface.
- new()
-
$pattern = XML::LibXML::Pattern->new( pattern, { prefix => namespace_URI, ... } );
The constructor of a pattern takes a pattern expression (as described by the BNF grammar above) and an optional HASH reference mapping prefixes to namespace URIs. The method returns a compiled pattern object.
Note that if the document has a default namespace, it must still be given an prefix in order to be matched (as demanded by the XPath 1.0 specification). For example, to match an element "<a xmlns="http://foo.bar"</a>", one should use a pattern like this:
$pattern = XML::LibXML::Pattern->new( 'foo:a', { foo => 'http://foo.bar' });
- matchesNode($node)
-
$bool = $pattern->matchesNode($node);
Given a XML::LibXML::Node object, returns a true value if the node is matched by the compiled pattern expression.
SEE ALSO
XML::LibXML::Reader for other methods involving compiled patterns.AUTHORS
Matt Sergeant, Christian Glahn, Petr PajasVERSION
1.70COPYRIGHT
2001-2007, AxKit.com Ltd.2002-2006, Christian Glahn.
2006-2009, Petr Pajas.
Contenus ©2006-2024 Benjamin Poulain
Design ©2006-2024 Maxime Vantorre